[net.auto.tech] Oil filters - Summary

junk@ur-tut.UUCP (Jan Vandenbrande) (03/06/86)

....
	First of all I want to thank everybody for the helpfull responces
about this subject. The question initially asked was whether there was
a difference between the various oil filters on the market. Some
filters (namely those that are supplied by the VW-Audi & Honda (?)
dealers) seem to have some springloaded mechanism, while other brands
do not. Well here is a brief summary on the responces:

1] The springloaded mechanism is a bypass valve. In case the filter gets
   clogged the filter will be bypassed. Better to have dirty oil circulating
   than no oil at all. Another person suggested that the valve serves to
   keep the oil in the circuits after shut off. At start-up the oil would
   be immediatly available.

2] There is a general distrust for filters sold by Sears etc. The only filter
   that kind off stood out were the filters made by FRAM. One claimed that
   they too have such a relief valve for the VW & Honda models. One person
   complained that the non-brand name filters (including FRAM) are not build
   as sturdily, and that he has to retorque them soon after an oil change.

Conclusion: I am going to wait until FRAM filters are on sale, and disect
one. I am also going to disect a regular VW filter and see how they differ.
I guess when you don't think that your filter gets clogged, that bypass
valve is not doing much. So normally it seems that there should not be
much harm to use a non-dealer filter if you change your oil frequently.
However, what are a few dollars compared to the potential engine damage?
How about "hidden" guarantees. If something breaks, and you haven't used
their stuff (even though unrelated issues) they might just void your
"hidden" warantee.
In the mean time I am going to stick to the dealer's oil filters.
Thanks for your replies,
Jan.

mberns@ut-ngp.UUCP (Mark Bernstein) (03/07/86)

**

I may get flamed for this, but I wonder if one can easily go a bit too
far, in a realistic sense, worrying about some of this.  

Under virtually all normal conditions, with a normal car, *changing the
oil frequently* (or at least as per mfrs.' recommendations), it seems 
rather far-fetched to imagine that an oil filter will get clogged up
so badly as to literally stop the flow of oil.  I wonder if mfrs. use
bypass valve type filters precisely because they KNOW that MANY people
AREN'T going to change their oil/filters as often as they should.  YOU
shouldn't worry about this; my dad (who can go 2 years before
remembering that, gee, I ought to have the oil changed), for instance, 
should.  With all due respect, I really do think that provided you do
change the oil and filter regularly there might be other, more important 
things to worry about re: your car (e.g. which tires to buy), and that it 
is silly to spend more money for the dealer's filter.  Fram, AC,
Purolator, etc. ought to do just fine.  Who do you think makes the
filters that the dealer sells (for more $), anyway?

Apart from the presence or absence of the bypass valve, I seriously
doubt that opening several filters for examination is going to reveal
anything meaningful that will affect a decision one way or the other.
Unless you're an automotive engineer.  What do you expect to find?
And even then, as I've indicated above, if you're conscientious about 
regular maintenance, the risk of ANY kind of engine damage due to using 
a filter other than the dealer's seems infinitesimal.  

--

Mark Bernstein, Univ of Texas at Austin, Speech Communication, Austin 78712
ARPA:  mberns@ngp.UTEXAS.EDU
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jin@hropus.UUCP (Bear) (03/10/86)

It's my impression that the bypass valve in an oil filter not only
serves to keep the oil flowing when the filter is clogged but it
serves to keep the oil flowing under low temperature conditions.
Not being an "expert" I don't know if this is true or makes sense.
Yes, I agree that tires etc. are more important, but discussion of
"minor" parts is networthy.
-- 
			Jerry Natowitz
			ihnp4!houxm!hropus!jin (official)
			ihnp4!opus!jin         (temporary) 
			Institute for the Study of Non-existent Phenomena

ugzannin@sunybcs.UUCP (Adrian Zannin) (03/11/86)

> Under virtually all normal conditions, with a normal car, *changing the
> oil frequently* (or at least as per mfrs.' recommendations), it seems 
> rather far-fetched to imagine that an oil filter will get clogged up

[]
  I always cringe when I hear people say that you should follow the 
manufacturer's guidlines for when to change the oil and filter.  First,
whenever you change the oil, you *must* change the filter too, even if it
isn't plugged solid.  The oil filter will hold about a quart of dirty oil,
which will defeat the whole purpose of changing the oil.  It will only
contaminate the old oil.  The old myth about "it's ok to change the filter
every other time" is just that, a myth.
   Second, you should *NEVER*, yes, *NEVER*, follow the manufacturer's 
recommendations on the amout of mileage between oil changes.  Many car
manufacturers suggest changing the oil around 10,000 miles.  To anyone
that knows about engine wear, this is rediculous!  You should *never*
leave the same oil in the car for more that 3,000 *maximum*.  For many
smaller engines, it is wise to change it every 2500 miles.  I know it
sounds like a pain in the neck to chage the oil that often, but when 
your car gets up around 70,000 miles, you'll see how it pays off.  My car
(a Toyota Corolla SR-5) has 94,000 miles on it and still has yet to
use (ie burn, leak) a drop of oil...


-- 
     Adrian Zannin
     SUNY at Buffalo Computer Science

..{bbncca,decvax,dual,rocksvax,watmath,sbcs}!sunybcs!ugzannin
CSNET:    ugzannin@Buffalo.CSNET
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mberns@ut-ngp.UUCP (Mark Bernstein) (03/12/86)

**
Xref: ut-sally net.auto:8469 net.auto.tech:925

> It's my impression that the bypass valve in an oil filter not only
> serves to keep the oil flowing when the filter is clogged ...
		....

> Yes, I agree that tires etc. are more important, but 
> discussion of "minor" parts is networthy.
  ^^^^^^^^^^ ^^  ^^^^^  ^^^^^ ^^ ^^^^^^^^^
-- 
>			Jerry Natowitz

Since this is apparently in reaction to my posting on this subject, let
me reply briefly:  I did not in any way mean to suggest that
discussion of "minor" parts (and I'm not sure I'd call an oil filter
by that term, in any case) is not networthy.  Only that perhaps a
person can (should?) pick and choose which aspects of maintaining or
equipping a car should be of MAJOR concern, worry, research, and
agony.  And that, in my view, one needn't worry very much about the
potential for disaster for the engine if one uses a *regular
brand-name* filter rather than the dealer's, and changes it regularly.
In short, my response was intended to say "...not to worry", rather
than to suggest that this wasn't worth discussing on the net.

Sorry for any misunderstanding.

--

Mark Bernstein, Univ of Texas at Austin, Speech Communication, Austin 78712
ARPA:  mberns@ngp.UTEXAS.EDU
UUCP:  ihnp4!ut-ngp!mberns  allegra!ut-ngp!mberns  gatech!ut-ngp!mberns
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hedden@atux01.UUCP (D. Hedden) (03/14/86)

In article <2925@sunybcs.UUCP>, ugzannin@sunybcs.UUCP (Adrian Zannin) writes:
> >   ... *changing the
> > oil frequently* (or at least as per mfrs.' recommendations)
>   I always cringe when I hear people say that you should follow the 
> manufacturer's guidlines for when to change the oil and filter.  First,
> whenever you change the oil, you *must* change the filter too, even if it
> isn't plugged solid.  The oil filter will hold about a quart of dirty oil,
> which will defeat the whole purpose of changing the oil.  It will only
> contaminate the old [sic] oil. ...
>   ...  Many car
> manufacturers suggest changing the oil around 10,000 miles.  To anyone
> that knows about engine wear, this is rediculous!  You should *never*
> leave the same oil in the car for more that 3,000 *maximum*.  For many
> smaller engines, it is wise to change it every 2500 miles.  I know it
> sounds like a pain in the neck to chage the oil that often, but when 
> your car gets up around 70,000 miles, you'll see how it pays off.  My car
> (a Toyota Corolla SR-5) has 94,000 miles on it and still has yet to
> use (ie burn, leak) a drop of oil...
Adrian, I have to agree with you about the futility of changing oil and
leaving a quart of dirty oil in the filter.  However, I have to ask "How
do you know your car wouldn't have done just as well with much less
frequent oil changes?"  Your posting implies that you have changed the
oil and filter every 2500-3000 miles, and that you have had satisfaction
from the car's not developing excessive (any) oil consumption.  But 
you don't say that you tried it the other way and had bad results :-).
I know most of us don't have money to do that sort of experimenting,
but I have had some experience in that area.  The last four cars I have
had got oil changes most of the time between 5000 and 10000 miles.
This wasn't by choice, it was just that my wife was the only one that
drove them and she didn't pay attention to milage for maintenance 
purposes, so things got done only when I happened to notice that it
had been a long time since the last time.  Each of these cars was sold
with more than 150,000 miles on them, and no oil problems.

This doesn't mean that I advocate this sort of abuse of engines, or
believe that this indicates all cars would do this well with care
coming this infrequently.  It is just saying that for these four part-
icular cars, the results were ok.

Incidentally, I change the oil and filter in my motorcycle, which is
my primary mode of transportation, about every 1500 miles.  My current
one is 12 years old with 143,000 miles, and has yet to need any repair
to the drive train.

   "The moving hand writes ..."

    Don

mberns@ut-ngp.UUCP (Mark Bernstein) (03/14/86)

**

On the same idea, but with a reverse twist:  I changed the oil and
filter in my 73 BMW 2002 religiously every 3500 or 4000 miles.  I
babied that engine for the eight years I had the car.  And
guess what?  By around 96,000 miles I was throwing enough blue smoke
on deceleration to require an engine overhaul.

Anyone care to generalize from *that* experience???   :-)

[I know, I know.... Someone's going to say "what did you expect from
THAT car?"   :-) ]

--

Mark Bernstein, Univ of Texas at Austin, Speech Communication, Austin 78712
ARPA:  mberns@ngp.UTEXAS.EDU
UUCP:  ihnp4!ut-ngp!mberns  allegra!ut-ngp!mberns  gatech!ut-ngp!mberns
       seismo!ut-sally!ut-ngp!mberns  harvard!ut-sally!ut-ngp!mberns

jimv@apollo.uucp (James Vienneau) (03/18/86)

>  I always cringe when I hear people say that you should follow the 
> manufacturer's guidlines for when to change the oil and filter.  First,
> whenever you change the oil, you *must* change the filter too, even if it
> isn't plugged solid.  The oil filter will hold about a quart of dirty oil,
> which will defeat the whole purpose of changing the oil.  It will only
> contaminate the old oil.  The old myth about "it's ok to change the filter
> every other time" is just that, a myth.
>  Second, you should *NEVER*, yes, *NEVER*, follow the manufacturer's 
> recommendations on the amout of mileage between oil changes.  Many car

What you say here USED to be true. Todays engines and SF rated oils are far superior
to what was around just 15 years ago. If anything, the recent articles I have read,
indicate that the car manufacturers are CONSERVATIVE in their change intervals.
Mobil publishes an excellent book on lubricants. Its 200-300 pages and sells for
around $30.00. As far as oil filters holding a quart of oil, thats no longer true
in MOST cases either. Most of todays cars have downsized filters that hold maybe a 
pint and several are mounted horozontally so the oil drains back into the engine
when shutoff. You can credit the EPA (for requiring unleaded gas) for a great deal
of the increase in change intervals. Lead was great for some things, but contaminated
oil quickly. 

I change my oil and filter every 12,000 miles and have driven every car I own (all GM) 
to >110,000 miles with no internal engine failures. I do use Mobil 1 synthetic oil,
but thats another story. ( 2 mpg boost w/Mobil 1 )

One other note, for an oil filter to say it meets manufacturers specifications, it
MUST contain a pressure relief valve and filter all particles over x microns. Buying
a manufacturers filter will not buy you anything over a good name brand 
(Fram, Purolator, Hastings, etc.) filter.

For the average person who plans on keeping their car <125,000 miles, does'nt tow 
anything and does'nt spend most of their time in city traffic and uses conventional
name brand oil, I would reccommend changes at the manufacturers intervals with the
oil filter replaced, chassis greased and tires rotated at each interval. This is the 
regiment that was followed on my wife's 76 Nova with 133,000 miles thats still going
strong today.                         

Just another mans opinions............................

J9N@PSUVM.BITNET (03/23/86)

      My last car, purchased new by my father in 1967, was a Chevy Malibu
Lines: 5
Xref: cbosgd net.auto:11325 net.auto.tech:964

wagon with a 283 V8 engine and Powerglide transmission. My father faithfully
changed the oil every 2000 miles.
      The car died when it was rusted beyond repair; the engine was still going
 strong after 234,000 miles......